Journal of Radio Electronics. eISSN 1684-1719. 2025. ¹11
Full text in Russian (pdf)
DOI: https://doi.org/10.30898/1684-1719.2025.11.36
A NEW METHOD FOR MEASURING MICROWAVE REFLECTION,
TRANSMISSION, AND ABSORPTION COEFFICIENTS
V.A. Vdovin, I.I. Pyataikin
Kotelnikov Institute of Radio Engineering and Electronics RAS,
125009, Russia, Moscow, Mokhovaya, 11, building 7
The paper was received November 13, 2025.
Abstract. A new method for measuring microwave reflection, transmission and absorption coefficients of ultrathin metal films is proposed, based on the use of micron-thick mica plates as substrates. When measuring the specified coefficients using this method, the substrate with the film deposited on it is attached to the flange of the waveguide in such a way that the metal film completely covers the aperture of the waveguide. A comparison was made between the measurement results obtained using this approach and the results obtained using a technique in which a glass substrate with a metal film is fixed inside the waveguide using elastic grains of radio-transparent polyethylene. It was found that the results of measurements using the new technique are in much better agreement with the predictions of the existing theory than the results of measurements using glass substrates. It was concluded that the previously found anomalies in the behavior of the microwave reflection and transmission coefficients of metal films in the region of their thicknesses greater than 10 – 25 nm are associated with a loose fit of the glass substrate with the film to the walls of the waveguide.
Key words: ultrathin copper films, microwave reflection and transmission coefficients, microwave absorption coefficient, impedance matching, size effect.
Financing: This work was supported by the Russian Ministry of Science and Higher Education through the state assignment of the Kotelnikov Institute of Radio Engineering and Electronics of the Russian Academy of Sciences (as a part of the “Pika” project).
Corresponding author: Vdovin Vladimir Aleksandrovich, vdv@cplire.ru
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For citation:
Vdovin V.A., Pyataikin I.I. A new method for measuring microwave reflection, transmission, and absorption coefficients of ultrathin metal films // Journal of Radio Electronics. – 2025. – ¹. 11. https://doi.org/10.30898/1684-1719.2025.11.36 (In Russian)